Jack



March 3, 1931. El E. sARR 1,794,798

JACK

Filed May 2, 1927 v REL\\\\\\\\\\\\\\\\\\\\\\\www!Illillllllllllllllllllllllll 9,3 Elma-r1 E.'5a-rr' UNE Patented Mar. 3, 131` Eni/inn i E. `SARR, or HURON, OHIO,

rres PATENT or-ice ASSIGNR F NE-HALF TO I-IIRALI C. WEITZMAN,

OF I-IURON, OHIO.

JACK

Application filed May 2, 1927'. -SerialvNd 188,347.

The present invention relates to improve-y ments in jacks, and theprimary object of the invention is to provide an improved typeof jackprimarily intended for use in connection with the legs of furniture suchastables of Vvarious characters, chairs, and the like,

for use as a leveling means therefor.

A further object of the invention is to proy vide a jack of thecharacter set forth embodying an elevating means for causing the lift totravel in a perfectly parallel relation with respect to its baseorsupporting section.

VA further objectief the invention isto prol vide an improved type ofjack as setforth construction as to permit of the device being formedrelatively shallow as to its over-al1 height.

A still further object of the invention is to provide an improved typeof jack for use in connection with table legs and the like,em bodyingnovel features ofassembly and features of construction whereby theinteriorfof the device isv rendered practically dust and,

moisture proof. Other obiects and advantages of the invennectionv withthe accompanying drawing forming a part of this specification/and inwhich drawing:

Figure l is a central vertical section through the improved jack takenlongitudi- 1 nally of the power screw and showing an element such Vas atable leg or the like supported n by the jack.

Figure 2 is a central vertical section through the jackonY the line 2-2of Figure l and looking in the direction lof the'arrows.

Figure 3 is top-,plan view of the base section fof the jack and showingthe `arrangement of the `lift or elevating means for movement of thecapsection away from the base section.

' Figure l is a perspective view of the inner side ofthe cap or liftsection and showing portions of the side wallsbroken away foi betterillustrating the specific construction of the cap section.

Figure 5 is a perspective view of one of the wedge members of theelevating means.

Figure 6 is an enlarged fragmentary detail view of the power screw.

v Referring to the drawing in detail, and wherein similar referencecharacters designate corresponding parts throughout the J several views,the letter A designa-tes the base section of the jack, B a cap or liftsection telelscopicallyassociated with the base section A, and C anelevating or lift means arranged` -in the base sectionA and acting uponthe cap section B-for movement thereof in a parallel plane away from thebase section A.y

Referring first to thebase section A, and

which may be cast from any suitable material such as brass', iron,aluminum or thelike, the` same in the vexample shown is square sli/'apein plan and embodies aflat base platelO provided at each marginal edgewith upstanding bordering side walls ll'.` Each of the side walls ll hasreduced upper portions l2 which form an externally extending shoulder13, while. the lower edge of each wall has aA flaringbase portionV 14which projects fora short distance belowthefunder surface of the baseplatelO as.clearlyfillustrated in Figures l tion will be apparent duringthe course of the following detailed description, take in con-f andv 2and which margin ally" extending Vba se 1portions will. provide a moreuniform bearing y17 respectively, and whichribs as will be observedginFigure 3 extend in parallel alignment with the power screw and from oneend wall l1 to the directly opposite end wall.

`While not entirely essential it is preferred that the outerslide ribs17 be disposed closely adJacent the opposite side walls 1l andk that.Yersely of :the tongues.

the inner ribs 16 be spaced but a short distance apart as illustrated inFigures 2 and 3. Formed on the base portion 14 of one of the side walls11 directly below the shoulder 13, is an outwardlyv extending` boss 18pro-vided with an opening or passageway V19 and which opening preferablyis of elongated formation in cross section with the major cross sectiondimension of the opening extending v ertica'l'ly or at a right angle tothe l'o-ngitndilllll axis of the side wall 11. Thus it will be seen thatthe base section A is of substantially box like formation and provides apocket 2O opening at the upper side :of the b i; like section.

Referring now tothe cap or 2lift section B and which is also preferably.formed of cast metal of a suitable nature, the same is adapted to betelescopically associated with the :base s Vtion A and embodies a flatcap plate being recessed at its outer face and inwardilgief 'itsmarginal edges for pri-)vida` a depression or socket 23, anddepezfid-ing from each marginal edge .of the cap plate, are ll-orderingflanges 2a of a depth substantially equal .tothe height of the reducedupper -portions 12 of the spaced side walls 11. As will lbe observed in.Figures 1 and 2, the inner sur faces of :the :depending iianges 24slidab'ly ngage the outer .surfaces of the upsta-ndli-ng portions 12 Aofthe base section A. This telescopical'ly lfitting of :the sections A andB serves to effectively exclude dust and dirt from entering `the pockety2O. Depending from the under side of the ea-p plate 22 and preferablycast integra-l -with'tlie section B, a series of parallel spaced Aa1')ar-t tongues being of greatest depth at their longitudinal centers andtapering therefrom in opposite directioi-is toward the lflanges 24 forAfori-ning oppositely incl-ined guide surfaces and 27 with the guidesurfaces of `the tongues aligning` one with the other tr-ans lon gitudnal l-y a rrai-l ged tions A and B are in assembled relation, extend insubstantial longitudinal yaligni'nent abo-ne each of the slide ribsprovided on the upper side ofthe base plate 10. 'It may here be well tostate thaftrthe overlapping ofthe flanges 2li and wall portions 12 also'acts as guide means for preventingrelative lateral shifting of thesections A and sl.

As ameans forretainingthesections A and B in assembled relation duringshipment, it is preferred that relatively short screws 28 be threadedthrough oppositefianges 24 as in Figure 2 and have their inner endsmovable in suitable elongated slot-S29 provided in the outer faces ofthe base wall portions 12. Those Screws 28 andslots .29 will permit ofrelative movement of .the soot-ions A and B but provost ,the Sectionsfrom boing .sopa

VThese tong-ues when ythe sec-Y .;able with the wedge members 32 and 34for movement thereof toward and away from one another alpen .rotation ofthe screw. The

wedge members 32 and 34 are of substantially 'ident-ical constructionand each embodies an clon-gated fiat tbottom portion '36 and an outerwall por-tion 37 which l extends along the outer longitudinal edge lofthe bofttom portion preferab'ly in right angular relation therewith.Formed at the upper side of the bottom portion 3G vand inner side of theouter wall'pc 1tion3,-a-ie inner and outer wedge stri-ps 3S and -39respectively each 'having correspondingly inclined `upper 'eel-ges l()which slope from 'the upper Yedge ofthe outer wall portion 37 towardtheinner edge ofthe 'bottom wall portion 36 as clearly 4 illflfustrated inFigures 1 and '5. The upper edge of the outer wall `-portion 37 ispreferably inclined to correspond with the inclination ofthe edges 4 0,These wedge strips 38 yand 39 and when the wedge members are in positionwithin the poeketw`20 are disposed above the respective slide ribs 16and 17 and have their inclined V upper edges aligning with the guidesurfaces 2 6 and 2 7 of the tongues 25. Thus it will 'be seen that .thefriction caused by the fsliding action of the wedge members 32 and ismaterially decreased by the edge contact between the tongues '25 andwedge Vstrips 3 8 and 39. Sliding friction between 'the wedge membersand 'base plate 11() is also decreased. by reason of the edge Contact ofthe -ri'bs 1 6 and 17 with the -nnder side of the wed-go .bottomportions 3 6. An arcuate shaped lug 42 depends from the. longitudinalcenter and inner edge of the bottom wedge portions 36 and extendsbetween the inner L ide ribs 1 6 for reinforcement of itl- 1e medial por'on of ithe wedges and also aiding lin presen ng later-al orlongitudinal shifting ofthe wedge members.

' The only differing charactenistics lbetween i the wedge =members132and 34, isthat the outer wall portion 37 of the wedge l n oember r311is'provided between the wedgestrips 39 with a threaded opening 44provided with left hand threads, While the outer wall portion 37 of theWedge member 32 is provdd between the Wodgostrps 3 9 with fa` threadedopening t6 of loss diameter-man that of the openiiigi and provided with:right Lhaadtlireads mee-,ves

shank portion 48k being arranged at the terminal of the power screw andbeing of less diameter than that of the shank portion 47 which isarranged adjacent the head or operating end of the power screw. TheshankA portion 48 of smaller diameter is provided with right handthreadsl for threaded connection with the right hand threaded opening 46while the shank portion 47 of larger diameter than the shank portion 48is provided with left hand threads for threaded engagement in the lefthand threaded opening 44 of the wedge member 34. The right and leftscrew threads of the shank portions 48 and 47 respectively are of thesame pitch so that upon rotation of the power screw each of the wedgemenibei's 32 and 34 will travel atan equal rate of speed. Formed at theouter end of the shank portion 47 is a thrust collar 50 which bearsagainst the inner side of the base section wall 1l at the inner end ofthe opening 19, and extending through the opening 19 from the collar 50is a stem portion 51 which projects for a distance past the outer end ofthe boss 18 for receiving a suitable operating knob 52 preferablyprovided with a wrench square 53. Thus it will be seen that the boss 18forms a bearing for the outer end of the power screw 35 and byv reasonof the knob 52 engaging the outer end of the boss, the power screw 1sheld against longitudinal movement when being rotated for movement ofthe wedge members 32 and 34. The opening 19 has been so formed to allowthe ready insertion of the stem portion 51 through the opening from theinner side of the base section during assembly, and after which the knob52fmay be connected with the projecting end of the stem. By so havingthe opening 44 of the wedge member 34` of greater diameter than theopening 46 ofthe wedge member 32, such will permit of the rcduced righthand threaded shank portion 48 to be readily inserted through theoppositely threaded enlarged opening 44 p for proper threaded connectionwith the right hand threaded opening ofthe wedge member 32.`

Thus it will be seen that upon rotation of the power screw that thewedge members 32 and f 34 may be drawn together or moved apart by thevpower screw embodying right and left threads of the same pitch but ofdifferent diameters. By having the threaded portions 47 and 48 of thesame pitch, it will be seen that the wedge members 32 and 34 will travelat equal rates of speed for movement of the traveler cap plate 22 in aperfectlyparallel position toward or away from the lbase plate 10.

` `l/Vhile the device is primarily intcn'ded'for useas a table jack, itlwill readily be apparent that the device may beusedfor various otherpurposes where a wedging orv lifting action is tobe'performed. From theforegoing description it will be apparent that an improved andv noveltype `.of jack has been `providedembodying rrelatively few and simpleparts so arranged as to reduce the over all height to a minimum andwinch-device'y operates under a novel principal' whereby the cap or liftsection movesin a plane parallel with the supporting or` base section'of the device. f1 i Changes in the shape, rsize and arrangement ofYparts may be made to the specific form of the invention herein shown andde- `scribed,' without departing from the spirit of ing a hollow basesection having a fiat bottom wall, a cap section slidably associatedwith the base sectionand having spaced narrow tongues'projecting intothe hollow base section and provided with oppositely inclined guidesurfaces, vwedge" members slidablyA mounted in the base section andengageable yone witlieach of the oppositely inclined guide surfaces ofsaid tongues, and a power screw carried by the base section and havingthreaded connection with each of said wedge members for imparting equaldegrees of movement thereto upon rotation of the power screw.

2. 'A jack of tlieclass described comprising a hollow base section, acap section telescopically fitting over the base section and havingparallel arranged tongues dependingfrom its under side and extendinginto the base section for providing oppositcly inclined guide surfaces,wedge members slidably mounted in the base section and each embodyingwedge strips having inclined edges for aligning with and engaging theinclined surfaces of said tongues, and a power screw mounted againstlongitudinal movement in the base section and having threaded connectionwith said wedge members for imparting equal degrees of movement theretoin opposite directions upon rotation of the power ing a base sectionincluding a base plate andi 'side walls, slide ribs formed 1n parallelrelation on the upper face of the base plate, a cap sectiontelescopically fitting over the side walls of the base section andhaving longitudinally arranged tongues provided with oppositely inclinedguide surfaces, ywedge Y members extending transversely of and restingupon said slide ribs and having' inclined upper edges engageable withthe oppositelyl inclined guide surfaces of said tongues, and

a power screw mounted against longitudinal movement in one side wall ofthe base portion in parallel-alignment With-saidguide ribs and havingthreaded connection with each of said wedge members for movement of themembers towardfandfaway tromione another upon rotation .of the powerserew.

4. Ajaekof the :class `deseriloed comprising a hase section embodyingaat base plate and .Oy upstanding side Walls, Aa cap section `embodyinga recessed top plate having depending flanges engagealole -with theouter surfaces of said hase :section Walls .and integral longitudinallyarranged tongues at y,the `under .side 1,15 ofthe top plate providedwith oppositel-y inclined guide surfaces, .along rtheir loweredgessaid'tongues fbeing oai greatest height at their longitudinal centersand tapering towand the top plate opposite Harige portions thereof,Wedge members slidable on the flat hase plate,

each including a series of Wedge strips having inclined upper edges forsurface contact with the oppositely inclined guide surfaces of saidtongues, `said Wedge members extend- 25 ing trzansverselyfof saidtongues, .and a power screw mounted against longitudinal movementiai-oneof the Side Walls -of the base portion and .extending inlongitudinal relation with said tongues .and having Aportions forthreaded connection with the Wedge members. for imparting equal degreesof Inovement thereto upon rotation of .the power Y screw.

ELMER E. SARE.

